From: Dmitry V. Levin <ldv@altlinux.org>
Date: Sat, 29 Jul 2017 23:27:52 +0000 (+0000)
Subject: ucopy: skip redundant tracee address truncation check
X-Git-Tag: v4.19~198
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ccba47d80a6975112272c568ec7bfe8c8dc18c24;p=strace

ucopy: skip redundant tracee address truncation check

* ucopy.c (vm_read_mem): Skip raddr != truncated_raddr check
if these variables have the same data size.
---

diff --git a/ucopy.c b/ucopy.c
index c2ec2c50..52cbfebd 100644
--- a/ucopy.c
+++ b/ucopy.c
@@ -67,10 +67,12 @@ vm_read_mem(const pid_t pid, void *const laddr,
 {
 	const unsigned long truncated_raddr = raddr;
 
+#if SIZEOF_LONG < SIZEOF_KERNEL_LONG_T
 	if (raddr != (kernel_ulong_t) truncated_raddr) {
 		errno = EIO;
 		return -1;
 	}
+#endif
 
 	const struct iovec local = {
 		.iov_base = laddr,